CHICAGO (STMW) — A middle-aged college student from the South Side was convicted of first-degree murder Thursday for stomping a fellow CTA commuter to death on a Green Line platform.

At least three commuters testified to seeing Anthony Jackson beat Sanchez Mixon in an unprovoked attack in the 300 block of East 43rd Street on March 16, 2013.

When one man from across the tracks at the 43rd Street station yelled at Jackson to stop, Jackson looked up and tried to justify the deadly assault by screaming, “I had to get crazy on him. I had to do it. He was following me,” Assistant Cook County State’s Attorney Yolanda Lippert said.

Jackson, 47, has a Chicago Police officer brother. His other brother, George Jackson III, a former federal prosecutor, was one of two lawyers representing him during his jury trial this week before Judge Stanley Sacks.

George Jackson III said his brother only went after 37-year-old Mixon because Mixon tried to rob him. Anthony Jackson also felt a metal object through a bag Mixon carried and assumed it was a gun, the defense attorney reminded jurors.

Prosecutors rejected claims that Mixon put his hand in Antony Jackson’s pocket or gave him any other reason to lash out to defend himself.

It was Anthony Jackson who started the physical contact by punching Mixon in the head after asking Mixon, “Hey why are you looking at me like that?” Lippert said.

Anthony Jackson, of the 500 block of East 67th Street, eventually knocked Mixon to the ground and started stomping and jumping on his head with both feet before other commuters called 911, prosecutors said.

The vicious beating was captured on CTA cameras.

The video footage “literally captured the face of death,” Lippert said in her closing arguments Thursday.

Anthony Jackson, a single father of five, was on his way to DePaul University­ — where he was studying computer science — before the deadly attack.

Anthony Jackson, whose family said he had a history of mental illness, turned himself in to police two days later.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2015. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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